This invention relates generally to ultrasonic imaging utilizing a transducer array and more particularly an ultransonic bidirectional transducer array in which each transducer can transmit and receive ultrasonic energy. The array may be included in an ultrasonic imaging system. In the system the transducers in the array are selectively scanned so that successive image samples provide ultrasonic imaging of moving objects.
Prior art systems for converting ultrasonic energy distributions having fine detail structure over an extended area into electrical form suitable for conversion to a visible display have not been satisfactory. Some of the systems are relatively insensitive, difficult to use, provide imprecise location of field sampling points and have poor response to transient signals. Other systems which overcome these disadvantages are unsatisfactory because they require that the objects viewed remain stationary for an extended period of time. In particular this fixed target requirement applies to systems which obtain the maximum possible resolution within the limits of aperture size and acoustic wavelength by transmitting and receiving from the same points within the insonified aperture.